Hot-air syringe.



no. 693,162. j Patented Feb. |902. i

A. w. scHnAMM ma. B.-w|| |=onn.

HOT AIR SYRINGE.

(Application led May 15, 190,1.)

no maar.)

1m: onlus PUERS co.. Pucouno., WASHINGTON, u. c,

'Nrran Stars .are-r einen.

ADOLPl-I W. SCHRAMM AND EDVARD B. WILEORD, OF PHILADELPHIA, PENN-SYLVANIA, ASSIGNORS TO ELECTRO n DENTAL MANUFACTURING COM- PANY, OFPHILADELPHIA, PENNSYLVANIA, A`CORPORATION OF NEW JERSEY. y Y

HOT-AIR SYRINGE.

SPECIFICATION forming part of Letters iPatentNo. 693,162, dated February11, 1902. Application filed May 15,1901: Serial No. 60,388. (No model.)

To @ZZ whom it may concern.-

Be it known that we, ADOLPH W. SCHRAMM and EDWARD B. VVILFORD, citizensot' the United States, and residents of Philadelphia,

Pennsylvania, have invented certain Improvements in Hot-Air Syringes, ofwhich the following is a specification.

Our invention relates to that class of hotair syringes in which theairin its flow tothe xo nozzle of the syringe passes over anelectrically-heated coil, one object of our invention-- being to soconstruct an instrument of this class as to simplify the operation ofthe same, a further object being to prevent injuryto i5 the coil byoverheating, and a still further object being to so convey the electriccurrent 1. Fig. 3 is a similar view showing one ofV 3o the parts in adifferent position from that represented in Fig. 2. Fig. 4 is atransverse section ou the line b b, Fig. 1. Figs. 5, 6, 7, and 8 aredetached views of parts of the syringe, and Fig;v 9 is a longitudinalsection illustrating a modification of the invention.

1 represents the handle of the syringe, which is made of hard rubber orother insulating material and has screwed into or otherwise attached toits llower end a projecting y 4o metallic plug 2, to which is secured,by means of a sleeve or ferrule 3, the upper end of the flexible tube 4,through which the supply of air is conveyed to the syringe. The handle 1is hollow and has screwed into or otherwise secured to the upper end ofit a tubular sleeve 5, into which in turn Ais screwed the lower threadedstem 6 of a plug 7, which is further secured to the sleeve 5 by means ofa nut 0 on the lower end of the threaded stem 6.

5o The plug 7 has formed in it two disconnected passages 10 and 11, theadjoining ends of which extend'outwardly and terminate oner above theother at one side ot' the plug. The upper threaded stem 12 ot' the plugreceives lthe lower threaded end of a hollow block 13 55A of vinsulatinginateriahto which is secured the shield14, which protects thetransparent casing 15, in which the heating-coil 1G is located. Theshield let carries at its outer end the delivery-nozzle 17 of thesyringe, andthe casing 15 has at its outer end an opening 19 in linewith the bore ot' said nozzle. The inner end of the casing 15 bears uponthe block 13, and the two form a easing for a chamber in which the airis heated by contact with the coil 1G. Theplug 7 is tapered, beinglarger in diameter 'atthe top than at the bottom, and surrounding saidplug is a sleeve 20, correspondingly tapered internally and maintainedin 7o snug contact with the plug by means of a spring-washer 21,interposed between the lower end of the sleeve 2O and the upper end ofthe sleeve 5. The sleeve 2O has in one side a recess or rchamber 22,andthe sleeve isv free to turn to alimited extent on the plug 7, so thatsaid chamber 22 may be caused to open communication' between thepassages 10 aud 11 of the plug or maybe turned away from the ends ofsaid passages, so as to cut oit the 8o iiow therethrough. The'sleeve 2Ohas at the upper end a projecting'pin 23, which enters a segmentalrecess formed in a washer 24, rest` ing upon the top of the plug 7 andprevented from turning by means of a pin'25, which pro- 85 jects fromthe top of said plug and enters an l opening 26 in thejwash'er. Thewasher 24 is in contact with another washer 27 at the lower en d of theinsulating-block 13,and said washer 27 is connected to oneterminal 29 ofthe heating-coil 16, the other terminal 30 of said coil being connectedto a block 31, which is secured to a ring 32, the latter surrounding thelower portion of the insulating-block 13 and being slit or severedthroughout a portion of 95 its circumference, so as to form a projectingspring-finger 33. 'A similar ring St, with projecting spring-finger 35,surrounds the upper end of the hollow insulating-handle 1 ot the syringeand is connected to a wire 36, einloo 'connection between the same.

bedded in the handle 1 and having its lower end confined between saidhandle and a nut 37on the plug 2, to which one of the electricalconducting-wiresis soldered orotherwise electrically connected,the otherof said Wires ben ing soldered or otherwise electrically connected tothe nut 9, which is applied to the lower end of the threaded stem 6 ofthe plug 7L The current thus passes from one of the conductors to theplug 2, nut 37, wire 36, ring 34, and spring-nger 35, and from the otherconductor to the nut 9, stem 6, plug 7, washers 24 and 27, thence to andthrough the heating-coil to the block 3l, ring 32, and springflnger 33,said spring-ngers 33 and 35 thus constituting terminals of an electriccircuit. Hence when these terminals are connected the current will iiowthrough vthe coil 16, properly heating the same, and when the connectionbetween said terminals is broken the flow of current through theheating-coil will cease. The making and breaking of the circuit iseffected by means of a ring 40, composed of insulating material andsecured to the sleeve 20, so as to move therewith, said ring having atone side a bar 4l, which when the ring is at onelimit of its movementcontacts with and provides connection between the spring terminallingers 33 and 35, as shown in Figs. 1 and 2, but when said ring 40 isat the other limit of its movement is moved away from said terminalfingers, as shown in Fig. 3, and therefore breaks the The sleeve 2O andring 40 move as a unit and practically form one part. Hence they may beregarded as a single sleeve and are so regarded in some of the claims.The chamber 22 in the sleeve 20 is Wider than the passages l0 and l1 inthe plug 7 and is so disposed in respect to said passages and to the bar41 of the ring 40 that it will open communication between the passagesbefore said bar 41 makes contact with the spring-terminals 33 and 35 andwill not cut oit communication between the passages 10 and 11 untilafter the bar 41 has been moved out of contact with said spring-fingers.Consequently the iiow of air through the heating-chamber of the syringeis established before the current is turned onto the heating-00H16 andcontinues until after the current has been cut olf from said coil,thereby preventing any overheating of the coil which might result it'thecurrent was turned onto the same before the {iow of air around thecoil began. Furthermore, the control both of the air-liow and of thecurrent is eected by the manipulation of but a single moving element ofthe instrument-namely, the ring 40-and all of the electric conductingelements of theinst-rument are thoroughly protected by insulatingmaterial, so that no accidental short-circuiting of the current can takeplace and no injury to the person handling the syringe can thereforeresult.

It is not necessary to the proper carrying out of our invention'that thecircuit-controlling switch should constitute a ring mounted so as to bepartially rotatable around the airplug, as a longitudinally-slidingring-such, for instance, as represented at 40L in Fig. 9- will attainthe same result, the circuit being broken and the iiow of air cut ottwhen said sleeve is in its lowermost position, as shown in Fig. 9, butthe flow ot air being lirst established and the circuit then closed byalifting movement of said sleeve.

The insulated conductors 42 and 43, i Yhereby the current is conveyed tothe syringe, pass through the iieXible air-supply tube 4 and areelectrically connected,respectively,to hollow metallic plugs 44 and 45,projecting from the opposite ends of a hollow block 46 ol insulatingmaterial, the plug 44 being connected to the outer endof the flexibletube 4 and the plug being intended to be connected to the tube wherebyair is supplied to the instrument and each of said plugs being providedwith a binding-post 47 for the attachment of the electricalconducting-wires. By this means all strain upon the electricalconductors 42 and 43 is prevented and liability of breaking theconnections between said conductors and the otherpartsvof the instrumentis overcome.

When it is desired to c ontrol the air-pressure at the nozzle, theforward limit of movement of the sleeve 2O may be such that the chamber22 will be carried forwardlybeyond the passages 1O and 1l of the plug 7,so that the low of air through said passages may be graduallyrestricted, the bar 41 remaining in contact with the spring-fingers 33and 35 during such regulating movement, so as to insure the continuedheating of the coil 16.

. Having thus described our invention,we claim and desire to secure byLetters Patentl. The combination in a hot-air syringe, of a hollowhandle, a casing inclosing the airheating chamber and containing anelectric heating-coil, a plug interposed between the handle and saidair-heating chamber, and having disconnected passages therein, and asleeve movable on said plug and having a chamber for openingcommunication between the passages of the plug.

2. The combination in a hot-air syringe, of a hollow handle, a casinginclosing the airheating chamber and containing an electricheating-coil, a plug interposed between the handle and said air-heatingchamber, and having disconnected passages therein, and a rotatablesleeve surrounding said plug and having a chamber for openingcom 1nunication between the passages of the plug.

3. The combination in la hot-air syringe, of the hollow handle, a casingcontaining an airheating chamber with electric 'heating-coil therein, aplug interposed between the handle and said air-heating chamber andhaving disconnected passages therein, electric conductor-terminals, of acircuit including the heating-coil and a sleeve movably mounted on theplug and having a chamber for con- IOO IIO

necting the passages thereof and a'bar for.

connectingsaid electric terminals.

4. The combination in avhotair syringe, of

the hollow handle, a casing containingan air-` heating chamber withelectric.heating-coil therein, a plug interposed between said handle andair-heating chamber and having disconnected passages therein, electricconductor-terminals, of a circuit including the heatro ing-coil and asleeve rotatable on the plug and a hollow handle, a casing containing anairheating chamber and havingan electric heating-coil therein, a pluginterposed between the air-heating chamber and the handle and forming.part of an air-controlling valve and zo also part of one of theelectric conductors for the heating-coil.

6. The combination in a hot-air syringe, of a hollow handle, a casingcontaining an airheating chamber and having an'electric heatz5 ing-coiltherein, a plug interposed between said air-chamber casing and thehandle and constituting part of the air-valve, and also part of one ofthe electrical conductors for the heating-coil, and a sleeve movablymount- 3o ed onsaid plug and constituting theother part of the air-valveand also a circuit making and breaking switch.

7. -The combination in a hot-air syringe, ot' a hollow handle, a casingcontaining an air- 3 5 heating chamber and having an electricheating-coil therein, a spring-finger mou nted upon said air-chambercasing'and constituting one of the terminals of an electric circuitcontainy ing the heating-coil, a similar spring-finger 4o mounted uponthe handle and constituting the other terminal of said circuit, and aninsulating-sleeve movably mounted between the airchamber casing and thehandle and having a bar which by the movement of Ythe sleeve is carriedinto and out of contact with said spring-terminals.

8. The combination in a hot-air syringe, of Ya hollow handle, a casingcontaining an airheating chamber and having an electric heat- 5oing-coil therein, a spring-finger mounted on the air-chamber casing andconstituting one of the terminals of the circuit containing theheating-coil, a similar spring-nger mounted upon the handle andconstituting the other terminal of said circuit, a plug interposedbetween the air-chamber casing and the handle and having disconnectedair-passages therein, and a sleeve movably mounted on sal-idv plug andvhaving av chamber for connecting 6o the air-passages of the same and abar for making and breaking connectionv between said spring-terminala 9.The combination in a hot-air syringe, of a hollowhandle, of insulatingmaterial, a

casing containing an air-heating chamber and having an electricheating-coil therein, a

sleeve of insulating material forming part of said casing, aspringcontact finger mounted on said insulating-sleeve and constitutingone ofthe terminalsot' the circuit containing the heating-coil, aspring-contact finger mounted upon the insulating-handle andconstituting the other terminal of. said circuit, and aninsulating-sleeve movably mounted between the insulating-handle and theinsulating-sleeve of the air-chamber casing and lhaving a barconstituting a circuit making and breaking switch, said movableinsulating-sleeve inclosing the spring-terminals so as to prevent accessthereto from the voutside of the instrument;

l0. The combination in a hot-air syringe, of

a hollow handle of insulating material, a casing inclosing anair-heating chamber and having an electric heating-coil therein, aninsulating-sleeve forming part of said -air-chamber casing a contactdevice mounted on said insulating-sleeve and forming one of theterminals ot the circuit containing the heatingcoil, a contact devicemounted on the insulating-handle and forming the other terminal of saidcircuit, a plug interposed between the insulating-handle and theinsulating-sleeve of the air-chamber casin g and having disconnectedair-passages therein, and an insulating-sleeve surrounding said plug andconstituting a means for controlling the iiow ofair through the syringe,and also surrounding, and provided with means for making and breakingconnection between, the terminals on the insulating-handle and on theinsulating-sleeve of the air-chamber casing.

ll. The combination in a hot-air syringe, of a hollow handle, a iexibleair-conveying pipe attachedthereto, a hollow insulating-block havingprojecting hollow plugs with bindingposts thereon, and flexibleelectrical conductors passing through the flexible air-pipe, andelectrically connected, one to one of said plugs and the other to theother of the same.

12. 'The combination of a hot-air syringe having an air-passage withelectric heatingcoil therein, circuit-terminals for said heating-coil,and a movable element constituting an air- Valve and a circuit makingand breakmovably mounted upon said plug and havi ing a channel forconnecting the passages of the latter, anda bar for connecting thecircuit-terminals, the distance between the channel and passages beingless than that between the bar and the circuit-terminals, whereby IIOIZO

ige

the channel and passages being less than that x5 between the bar and thecircuit -tern1inals, whereby communication between the air-passages willbe established before the bar makes contact with the circuit-terminals.

In testimony whereof we have signed our 2o names to this specificationin the presence of two subscribing witnesses.

ADOLPH WV. SCHRAMM. EDVARD B. 7WILFORD.

Witnesses:

F. E. BEoHToLn, Jos. H. KLEIN.

